Quick answer: Commercial glass condensation has three causes: surface condensation (humidity on the cold glass surface — normal), interior condensation between rooms (HVAC issue), or condensation inside the insulated glass unit cavity (IGU seal failure). The first two are operational issues. The third is a warranty issue requiring lite replacement.
When warm humid air contacts a cold glass surface, water condenses. Common in Florida on cooler nights or when AC is set very low. Not a glass defect. Solutions: increase room temperature, reduce humidity (dehumidifier), or upgrade to higher U-factor (more insulating) glass to keep the interior surface warmer.
Same physics: warm humid outside air meets cold glass surface (cold from AC inside). Common in Florida in the morning. Not a defect; will dissipate as outside warms. Solutions: not really needed — this is normal. Persistent outside condensation indicates very effective low-E glass (which is good).
This is IGU seal failure. The hermetic seal between two glass lites has failed, allowing moisture vapor inside the sealed cavity. Visible as: fogging, water droplets, or mineral residue inside the cavity (you can't wipe it off). Glass cannot be repaired — the lite must be replaced. Covered under most 10-year IGU warranties.
Touch the moisture: if it wipes off, it's surface condensation (Type 1 or 2). If it doesn't (because it's inside the cavity), it's Type 3 IGU failure. Time of day matters too: Type 1 and 2 happen at specific times of day; Type 3 is constant.
Document with photos including the date stamp. Contact the original glazier within 30 days of noticing. ACG handles all warranty coordination for projects we installed. Replacement is the only fix — there's no way to re-seal a failed IGU in the field.
IGU seals fail due to: (1) excessive temperature cycling (badly installed IGUs in high-stress applications). (2) Standing water at the IGU edge (poor weeping detail). (3) Building movement exceeding design tolerances. (4) Age — even properly made IGUs fail at 20-30 years. Quality installation extends the timeline significantly.
Three causes: (1) surface condensation when humid air meets cold glass — normal. (2) Condensation between conditioned and unconditioned space — HVAC issue. (3) Condensation inside the IGU cavity — seal failure, warranty issue.
No — if condensation is inside the sealed insulated glass cavity, you cannot wipe it off (it's behind the inner glass surface). This indicates IGU seal failure and the lite must be replaced.
Surface condensation (Type 1 and 2) is normal and not a defect. Condensation inside the IGU cavity (Type 3) is IGU seal failure — typically covered under a 10-year manufacturer warranty.
A properly fabricated and installed IGU should last 20-30 years before seal failure. Florida's high humidity and temperature cycling can shorten this slightly compared to milder climates.
No — failed IGUs cannot be re-sealed in the field. The hermetic seal must be re-created in a controlled factory environment, which is not practical. The entire lite must be replaced.
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